Glenoid Rim Lesions Associated with Recurrent Anterior Dislocation of the Shoulder

Abstract

Twenty-five shoulders with recurrent instability and associated anterior glenoid rim lesions were reviewed to 1) develop a classification system of the lesions, 2) evaluate radiographic techniques in detecting the lesions, and 3) analyze the outcome of surgery. Lesions were classified into three types: Type I, a displaced avulsion fracture with attached capsule; Type II, a medially displaced fragment malunited to the glenoid rim; and Type III, erosion of the glenoid rim with less than 25% (Type IIIA) or greater than 25% (Type IIIB) deficiency. Lesions were detected by plain radiographs (19 shoulders) or supplemental CT-arthrograms (12 shoulders) or both. In 16 Type I fractures, both the bony fragment and capsule were reattached to the glenoid rim. In five Type II and three Type IIIA lesions, only the capsule was repaired to the remaining glenoid rim. In the one Type IIIB lesion, a coracoid transfer was performed. At an average followup of 30 months, 22 shoulders (88%) had satisfactory results without recurrent instability, whereas three shoulders (12%) had postoperative redislocations. The majority of recurrent anterior dislocations with associated glenoid rim lesions can be treated by suturing the fracture fragment or capsule or both to the glenoid rim and addressing associated capsular laxity.